This invention is in the field of auger conveyors and in particular such auger conveyors wherein one portion of the conveyor pivots with respect to another portion.
There are common applications where an auger conveyor comprises two sections oriented at an angle to each other, and where the flighting shafts of the sections are connected to each other such that they turn together. It may be further required that the first and second sections pivot with respect to each other while the augers rotate. Such applications include combine grain tank filling augers as illustrated in U.S. Pat. No. 6,248,015 B1 to Rayfield et al., and grain cart unloading augers as illustrated in U.S. Pat. No. 6,042,326 to Thomas et al. The application is also typical in combine unloading augers, as illustrated in U.S. Pat. No. 3,664,525 to Herbstofer, U.S. Pat. No. 6,247,886 B1 to Signer et al., U.S. Pat. No. 4,662,812 to Busboom et al., and U.S. Pat. No. 4,093,087 to DeCoene.
The angle between the two auger sections in the device of Rayfield et al. is shallow enough to allow the connection between the flighting shafts of the two sections to be made with a universal joint, however with the sharper angles of Signer et al. and Thomas et al., a gearbox is required. The addition of a gearbox in the middle of the flow of granular material retards the flow of material and reduces the capacity of the auger conveyor. Where a gearbox is used, the angle between the two auger conveyor sections is fixed, thereby limiting the flexibility of the apparatus.
In the apparatuses of Busboom et al. and DeCoene, an intermediate section of auger conveyor is used such that the required angle between the first and second sections is provided by a smaller angle between the first section and the intermediate section, and again between the intermediate section and the second section. A universal joint at each end joins the auger flighting shafts together. Where a single universal joint would not provide satisfactory service when operated at the angle between the first and second sections, that angle can be reduced by half when splitting it between two universal joints.
In the auger apparatus of Busboom et al. a bottom cross auger and the intermediate section are fixed in position, while the straight unloading auger section pivots about an oblique axis so that the auger can move from a transport position up and forward to an operating range of positions. The discharge end of the unloading auger moves quite sharply up and down as it moves forward and rearward.
In the apparatus of DeCoene a bottom cross auger is fixed and the intermediate auger and unloading auger pivot about an axial plane that is in the middle of the intermediate auger. With this pivot plane location, the intermediate auger moves up and down and fore and aft when the unloading auger pivots. The tube on the intermediate section must be much larger than the auger flighting to accommodate this movement, reducing efficiency of the auger. Much grain is wastefully moved sideways as it is not confined by a close tubing wall. As in the apparatus of Busboom et al. the discharge end of the unloading auger moves quite sharply up and down as it moves forward and rearward.
U.S. Pat. No. 5,409,344 to Tharaldson and U.S. Pat. No. 5,980,189 to Rubner disclose self-unloading hoppered grain carts similar to Thomas, but unlike Thomas the cart container is hoppered to a central sump such that a cross-auger at the bottom is not required. Both comprise a first upright conveyor section to carry grain upwards and outwards from the sump to an upper location outside the container where same falls into a second lateral conveyor section that pivots with respect to the cart. Each section is a separate conveyor requiring separate drives, mounts, and the like.
It is an object of the present invention to provide an improved self-unloading container apparatus mounted on a vehicle and having an auger conveyor with a discharge end that can be pivoted from a transport position to operating positions extending put to one side of the vehicle so as to discharge the contents of the container into a transport vehicle.
It is a further object of the present invention to provide such an apparatus wherein the discharge maintains a more consistent vertical position while moving forward and backward in the operating range. It is a further object of the present invention to provide such an apparatus wherein obstruction of the auger tube is reduced, and capacity is thereby increased.
It is a further object of the present invention to provide such an apparatus wherein the container includes a floor sloped down to a sump located in a central portion of the container, and comprising an integrated auger apparatus to carry material from the sump to a discharge that can be moved to a range of operating positions extending laterally from the container.
The present invention provides, in one aspect, a self-unloading container apparatus mounted on a vehicle for travel in an operating travel direction. The apparatus comprises a container mounted on the vehicle and a fixed upright auger tube mounted in the container and oriented such that a lower intake end thereof is located in the bottom of the container. The upright auger tube slopes upward and outward, transverse to the operating travel direction, to an upper output end thereof located outside the container adjacent to an upper side wall of the container, and an upright flighting shaft is positioned inside the upright auger tube. An intermediate auger tube is pivotally attached at an input end thereof to a top output end of the upright auger tube so as to pivot about a pivot axis on a pivot plane, and an intermediate flighting shaft is positioned inside the intermediate auger tube. A lateral auger tube is attached at an input end thereof to an output end of the intermediate auger tube at a fixed oblique angle, and a lateral flighting shaft is positioned inside the lateral auger tube. A universal joint connects an input end of the intermediate flighting shaft to the upright flighting shaft such that a center of the universal joint is located substantially on the pivot plane and pivot axis, and a constant velocity universal joint connects an output end of the intermediate flighting shaft to the lateral flighting shaft such that a center of the constant velocity universal joint is located substantially at the intersection of axes of the intermediate and lateral auger tubes. A control is operative to pivot the intermediate auger tube with respect to the upright auger tube from a transport position, wherein the lateral auger tube is substantially aligned with the operating travel direction, to an operating position, wherein the lateral auger tube extends outward from the container transverse to the operating travel direction. A drive is operative to rotate the flighting shafts.
The apparatus of the invention is particularly suited to a hopper bottom grain cart. The intake end is located in a central sump and an upright section slopes outward to a position outside the container, as is generally required in these hoppered containers, and the slope also reduces the angle required between the upright and lateral sections to bring the lateral section to a shallow angle with respect to the horizontal.
In a second aspect the invention provides a self-unloading hopper bottom grain cart comprising a container having a hopper floor sloping down to a centrally located sump. A fixed upright auger tube is mounted such that a lower intake end thereof is substantially in the sump and the upright auger tube slopes upward and outward, transverse to the operating travel direction, to an upper output end thereof located outside the container adjacent to an upper side wall of the container, and an upright flighting shaft is inside the upright auger tube. An intermediate auger tube is pivotally attached at an input end thereof to a top output end of the upright auger tube so as to pivot about a pivot axis on a pivot plane, and an intermediate flighting shaft is inside the intermediate auger tube. A lateral auger tube is attached at an input end thereof to an output end of the intermediate auger tube at a fixed oblique angle, and a lateral flighting shaft is inside the lateral auger tube. A universal joint connects an input end of the intermediate flighting shaft to the upright flighting shaft such that a center of the universal joint is located substantially on the pivot plane and pivot axis. A constant velocity universal joint connects an output end of the intermediate flighting shaft to the lateral flighting shaft such that a center of the constant velocity universal joint is located substantially at the intersection of axes of the intermediate and lateral auger tubes. A control is operative to pivot the intermediate auger tube with respect to the upright auger tube from a transport position, wherein the lateral auger tube is substantially aligned with an operating travel direction, to an operating position, wherein the lateral auger tube extends outward from the container transverse to the operating travel direction. A drive train is adapted for connection to a towing vehicle and is operative to rotate the flighting shafts.
The pivot axis can be oriented such that the first and intermediate flighting shafts are aligned, reducing stress on the universal joint connecting the two. The constant velocity universal joint allows a sharper angle between the intermediate and lateral tubes such that the lateral tube can be oriented near the horizontal for maximum reach. Where desired, the pivot axis can also be oriented such that the discharge end of the auger conveyor moves up and down as well as laterally with respect to the intake end of the conveyor. By re-orienting the pivot axis, a wide range of movement can be achieved at the discharge end of the lateral tube.
The constant velocity universal joint, combined with the small operating angles that are achieved on the standard universal joint, provide a very smooth operating auger conveyor throughout a significant operating range of movement of the discharge end of the lateral tube. A wider operating range and steeper angles between the upright and lateral tube can be achieved by using a constant velocity universal joint at each end of the intermediate flighting shaft. The apparatus is simple and economical to manufacture and maintain.